Tahseen claims to have killed at least 173 fighters since joining the Shia militia in May 2015, but that number could have gone substantially higher since the filming of this video.

His first mission is to push ISIS from the Makhoul Mountains, and he’s determined to get as many kills as possible before the war is over. Tahseen’s story has also inspired others to take up arms against the enemy.

This video shows the veteran shooting militants in the mountains of Iraq.